Special Features: The Environment

Research on Watershed/UrbanRegeneration in Accord with Nature ....
YASUDA Yoshiya
Head of the River Environment Division, Environment Department

1. Background and Goals of the Research
The environment of a city where people spend their lives
receives generous benefits and is greatly influenced by thewater cycle, material cycles dependent on water, and theecosystem of the watershed that surrounds the city.
Urbanization and inadequate management of forests inwatersheds in Japan have severely disrupted water and material cycles and ecosystems, resulting in serious deteriorationof urban environments.
To restore an urban environment so its residents canenjoy the beneficence of nature, it is essential to establish
measures based on the perspective of an entire watershed toclarify the state of the environment, conserve nature, forests,
and farmland, to curb environmental pollution, to conserve
water environments and create ecological networks, and topractice national land management to restore cities in a
symbiotic relationship with nature through restoring thewater cycle and the ecosystem. The goal of this research, athree-year research project that will begin next year, is tocreate watersheds and cities in a symbiotic relationship withnature. In advance of the start of full-scale research, thisreport describes the content of the research and the resultsthat it is expected to achieve.
As research in the environmental field that is a priority ofthe Council for Science and Technology Policy, it is stipulated by the Research Initiative for Technologies for theWatershed/Urban Regeneration in Accord with Nature, andwill be undertaken jointly with the Ministry of Agriculture,Forestry, and Fisheries and the Ministry of the Environment.
2. Content and Structure of the ResearchThis research will involve 6 themes
under 4 research programs. These themes
will be carried out by the Environment
Department, Water Quality Control
Department, and River Department (Fig.
1).
The following are the research policies and the outputs anticipated at thistime for each theme in each program.
(1) City and watershed environment
monitoring program
To resolve problems that occur inwatersheds and cities, monitoring will bedone to clarify and evaluate the functions
and actual state of the water and material
cycles and ecosystems in watersheds andcities and a data base will be established.

[1] Monitoring and the clarification and evaluation offunctions and actual conditions
The effects on bodies of water and ecosystems in watersheds and cities of population increase, changing land use,changes in the quantities of materials used and discharged
will be clarified. And the actual state of water and material
cycles and ecosystems will also be clarified through monitoring (Figs. 2, 3).
[2] Provision of a data base
Basic data concerning the topography, geology, rainfall,
i. City and watershed environment monitoring program
1. Monitoring and the clarification and evaluation of functions and actual conditions
2. Provision of a data base[Environment Department, Water Quality Control Department, River Department]

ii. City and watershed management model development program
3. Development of a watershed and city management model[Environment Department]

iii. Nature symbiosis technology development program
4. Water and material cycle (systems), ecosystem, urban environment restoration
technologies[Environment Department, Water Quality Control Department, River Department]

iv. Nature symbiosis type society creation scenario preparation andimplementation program
5. Development of humanities and social science based analysis and evaluation
systems and research on policy scenarios
6. Enactment and implementation of the watershed/urban regeneration program(Examples)[Environment Department, Water Quality Control Department, River Department]

Fig. 1. Research Programs, and Research Themes.

Harmful atmosphericpollution
Factory
exhaust gas

Heat island
phenomenon

Water and materials
supplied from upstream

Accumulatedon roofs
Rainwater runoff
from forests and fields
Roads (automobile exhaust gas,road drainage water, road surface
material)
Inflow from household wastewater(household products, medicines,excreta, etc.)

Discharge of rainwaterfrom urban areas

Groundwater
Water treatment plantRaw materials and products

Supplied to the public
water supply system
Waterintake
Drainage from urban area
Ordinary homes

Dilution

Direct discharge of water fromfactories etc. into bodies of water

Discharge
from factories
TreatedsewerageTransformation
Waste material
from homes, factories, etc.

Primary production
Sludge(environmental impact)
Algae bed/tideland

Returned as food for people
Public body of water

Fig. 2. Monitoring and Clarifying the State of Water and Material Cycles.

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Special Features: The Environment

1. Inland ecosystem
Present
Animal habitat

Aquatic insects
Frogs
HeronsSandbanks
Hawks

Ecosystem viewed from the watershed
perspective

Change in the ecosystem over time
(Changes in biota and the basic environment)

Raccoon dogs
Agrarian villages innatural surroundings

Landscape
category
Watershed

Past

Aquatic insects
Frogs

Effects of human activities◆ Population growth◆ Urbanization
environment◆ Urbandeterioration
structure◆ Changingof industryof forests, fields, and◆ Shrinkage
shorelines
methods of managing◆ Changing
forests and fields
methods of controlling◆ Changing
irrigation water◆ Construction of public facilities

2. Aquatic ecosystems
Ecosystems in rivers, lakes/marshes, coastlines, and the seaFig. 3. Monitoring and Clarification of the State and Functions of Ecosystems.

population, land use, ecosystems, population
Topography, geology,
G I S
soilrainfall, atmosphere,dynamics, changes in land use, etc. in a modelclimatewatershed will be obtained, incorporated in a
Watershed data baseSocial conditions
geographical information system (GIS), thenPopulation Land use
used to develop water and material cycle models
and ecosystem models to create a base for policy
Integrated modelForest, field, andscenario analysis (Fig. 4).
coastal region indices
Water and(2) City and watershed management model
Ecosystem material
Watershed/urban
model
development program
cycle models
River, groundwater
Regeneration
Sewer systems
in Accord with
[3] Watershed and city management model
Pollution sources,
Nature Program
drainage Water use
Humanities and socialconstruction
science analysis andevaluation systems
The effects of changes in watersheds andVegetation
cities on water and material cycles and ecosysAnimal habitats
Scenario analysis
tems will be predicted to construct water andmaterial cycle models and ecosystem models that
Biodiversity(including thegenetic level)
can be used to quantitatively estimate future
measures in order to assess their value. This will
Policy scenarios
Construction of systems to share and use information
be accompanied by a study of an integrated
model that can integrate the two models in aFig. 4. Conversion of Basic Data to GIS and its Application.
geographical information system (GIS).
(3) Nature symbiosis technology development program
tionship with nature restoration program, research based on[4] Technology to restore water and material cycle
the humanities and social sciences will be undertaken to(systems), ecosystems, and urban environments.
develop technologies needed to enact, analyze, and evaluate
Water environment restoration technologies to resolve
specific policy scenarios, methods of evaluating the public
problems with water and material cycles etc., and conservaacceptance of policies, and methods of forming a consensus
tion and restoration technologies for ecological networks
that account for resident participation and the fairness ofthat will resolve ecosystem problems will be developed.
procedures etc.
(4) Nature symbiosis type society creation scenario[6] Enactment and implementation of the Watershed/Urban
preparation and implementation program
Regeneration Program (Examples)[5] Development of humanities and social science basedSpecific research will be undertaken to plan and impleanalysis and evaluation systems and research on policy
ment the model watershed/urban regeneration program. The
scenarios
goals of the restoration program are "restoration of contact
To enact the watersheds and cities in a symbiotic relawith nature and water and material cycles," "conservation
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Special Features: The Environment
prepare for next year, a GIS Study Group, ConsensusFormation Research Committee, and Urban Environment
Restoration Research Committee have been formed. A workshop for researchers was held on February 9th with the cooperation of the Ministry of Agriculture, Forestry, andFisheries and the Ministry of the Environment.

and restoration of water environments and ecosystems," and"restoration of the water, greenery, and environment ofcities." Scenarios for these will be prepared for each watershed and city (Figs. 5, 6).

3. Efforts During the Year
Activities related to this research have partly begun. To· Land use· Non-point source measures· Forest and farm field
conservation· Waste management· Rationalization of water use· Restoration and conservationof agrarian villages
in natural surroundings· Conservation ofwater resources

Increasing water
quantity

Appropriate mountain
forest management

Watershed

Mitigating the heat island
phenomenon and preventing
urban flooding

Preventing discharge ofagricultural chemicals and fertilizer

Urban area

Rainfall

Water treatment plant

Farm land

Rainwater pipe

Rainwater
purification measure
Installation of buffer zone
(wetlands)
Management of fertilization

Underground seepage
Control of roadsurface drainage

Sewage pipe

Abundant ecosystems

Restoration andcreation ofwaterside space

Safe drinking water

Sewer Systems· Improvement of combined
sewer systems· Removal of environmental
contaminants· Advanced treatment

Rivers· Improvement of river
flow regime· Natural restoration rivers· Waterside space in cities· Conservation and restorationof wetlands· River water purification· Sediment control

Mountains

Providing rivers in richnatural settings
Safe recreational
water

Improvement ofcapacity to purify
factory wastewaterSea

Sea areas· Blue tide and red tide measures· Bottom sediment improvement· Conservation and creation of goodquality sandy shorelines· Waterside space in cities· Conservation and restoration oftidelands, algae beds,
and aquatic bird feeding
grounds
Factory district

Restoration ofecosystems

Restoration of natural purification functions and reduction of loads• Shorelines where people can fish or swim
• Guaranteeing biodiversity by water quality improvements and habitat improvement• Improvement of amenities in urban shoreline space• Guaranteeing a safe and palatable water supply
OthersFig. 5. Sample Restoration Program (1) (Conservation and Restoration of Water Environment and Ecosystems).

Provision of the information
infrastructure (GIS)

Enacting ecosystem network
plans･ Planning the provision of
ecological infrastructure(including infrastructure torestore nature), planning controlof obstructive factors

Water and material
cycles(watershed cyclemodel)

Incentives for the regulationof land use･ City planning, agricultural landplanning etc.

CityBiodiversity
Land use(Landscapemanagement)

Communication
tools
Restoration
andcreationof multi-function
living space(Roads, rivers,and parks)

Load reduction
Hazardous material
management
Reduction ofsuspended particulatematerial

Consensus formation
Citizenparticipation

Mitigation of the heatisland phenomenon

Landscapeformation

Habitat network
formation

Providing and managing
the ecological infrastructure･ Improving environmental
properties of public spaces,
pervious pavement, rainwater
storage, and reuse of treatedwater, etc.
Participation by citizens andcorporations･ Reforestation of private land,
planting rooftop vegetation,
restoration and conservation ofagrarian villages in natural
surroundings･ Scenery agreements etc.
Urban restoration･ Establishment of technologies
and enactment of urban restorationplans to reduce the production of
hazardous atmospheric pollutants
and mitigate the heat island effect

OceanFig. 6. Restoration Program Example (2) (Restoring Water, Greenery, and the Environment in Cities.

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